Hacks to make HW decode work on linux via libva.

content/common/gpu/media/vaapi_h264_decoder.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <dlfcn.h>
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 256 matching lines @@
 
 VaapiH264Decoder::DecodeSurface::~DecodeSurface() {
   // Unbind surface from texture and deallocate resources.
   if (glx_pixmap_ && make_context_current_.Run()) {
     glXReleaseTexImageEXT(x_display_, glx_pixmap_, GLX_FRONT_LEFT_EXT);
     glXDestroyPixmap(x_display_, glx_pixmap_);
   }
 
   if (x_pixmap_)
     XFreePixmap(x_display_, x_pixmap_);
+  XSync(x_display_, False);

[Ami GONE FROM CHROMIUM, 2012/09/07 10:04:21]

Without this, rendering_thread.Stop() in vdatest triggers this:

X Error of failed request:  GLXBadPixmap
  Major opcode of failed request:  135 (GLX)
  Minor opcode of failed request:  23 (X_GLXDestroyPixmap)
  Serial number of failed request:  585
  Current serial number in output stream:  590

on thread shutdown.  I suspect a driver bug, but this method is called
sufficiently infrequently that I can live with this hack.  WDYT?

[Pawel Osciak, 2012/09/07 15:49:13]

Could be a driver bug and/or us not being in correct/valid GLX context at the
time of destroying the glx pixmap. Is make_context_current_ above at l.270
working for you?

I agree this XSync would not be a big deal being here only, although I'm more
worried about leaking memory with the above error (unless it's because of
double-freeing, here and somewhere in the driver perhaps).

[Ami GONE FROM CHROMIUM, 2012/09/12 00:53:10]

It must be, or else the failing opcode wouldn't be getting called :)
yes, my suspicion is on the driver.

 }
 
 void VaapiH264Decoder::DecodeSurface::Acquire(int32 input_id, int poc) {
   DCHECK_EQ(available_, true);
   available_ = false;
   input_id_ = input_id;
   poc_ = poc;
 }
 
 void VaapiH264Decoder::DecodeSurface::Release() {
@@ skipping 1996 matching lines @@
       VAAPI_SyncSurface &&
       VAAPI_BeginPicture &&
       VAAPI_RenderPicture &&
       VAAPI_EndPicture &&
       VAAPI_CreateBuffer &&
       VAAPI_DestroyBuffer &&
       VAAPI_ErrorStr;
 }
 
 }  // namespace content